She also wore the tiara in December 2016, at the same Buckingham Palace event previous year, where she donned a bright red lace Jenny Packham gown. In July of this year, Kate was spotted wearing it again at a state dinner with Spain's King Felipe and Queen Letizia.

Though the tiara was one of Diana's favorites, it was actually made for Queen Mary in 1914 by Garrard, jeweler to the British royal family.